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OBJECTIVES: Assessing a posterior fossa tumour in an adult can be challenging. Metastasis, haemangioblastoma, ependymal tumours, and medulloblastoma are the most common diagnostic possibilities. Our aim was to evaluate the contribution of magnetic resonance spectroscopy (MRS) in the diagnosis of these entities. METHODS: We retrospectively evaluated 56 consecutive patients with a posterior fossa tumour and histological diagnosis of ependymal tumour, medulloblastoma, haemangioblastoma, and metastasis in which good-quality spectra at short (TE 30 ms) or/and intermediate (TE, 136 ms) TE were available. Spectra were compared using the Mann-Whitney U non-parametric test in order to select the spectral datapoints and the intensity ratios that showed significant differences between groups of lesions. Performance of these datapoints and their ratios were assessed with ROC curves. RESULTS: The most characteristic signatures on spectroscopy were high choline (Cho) in medulloblastoma (p < 0.001), high myoinositol (mIns) in ependymal tumours (p < 0.05), and high lipids (LIP) in haemangioblastoma (p < 0.01) and metastasis (p < 0.01). Selected ratios between normalised intensity signals of resonances provided accuracy values between 79 and 95% for pairwise comparisons. Intensity ratio NI3.21ppm/3.55ppm provided satisfactory discrimination between medulloblastoma and ependymal tumours (accuracy, 92%), ratio NI2.11ppm/1.10ppm discriminated ependymal tumours from haemangioblastoma (accuracy, 94%), ratio NI3.21ppm/1.13ppm discriminated haemangioblastoma from medulloblastoma (accuracy, 95%), and ratio NI1.28ppm/2.02pmm discriminated haemangioblastoma from metastasis (accuracy, 83%). CONCLUSIONS: MRS may improve the non-invasive diagnosis of posterior fossa tumours in adults. KEY POINTS: ⢠High choline suggests a medulloblastoma in a posterior fossa tumour. ⢠High myoinositol suggests an ependymal lesion in a posterior fossa tumour. ⢠High lipids suggest a metastasis or a haemangioblastoma in a posterior fossa tumour.
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Colina/metabolismo , Hemangioblastoma/diagnóstico , Neoplasias Infratentoriales/diagnóstico , Inositol/metabolismo , Espectroscopía de Resonancia Magnética/métodos , Meduloblastoma/diagnóstico , Adulto , Biomarcadores de Tumor/metabolismo , Diagnóstico Diferencial , Femenino , Hemangioblastoma/metabolismo , Hemangioblastoma/secundario , Humanos , Imagen por Resonancia Magnética/métodos , Masculino , Meduloblastoma/metabolismo , Meduloblastoma/secundario , Metástasis de la Neoplasia , Curva ROC , Estudios Retrospectivos , Adulto JovenRESUMEN
BACKGROUND AND PURPOSE: Although there is generally thought to be a 2% to 4% per annum rupture risk for brain arteriovenous malformations (bAVMs), there is no way to estimate risk for an individual patient. METHODS: In this retrospective study, patients were eligible who had nidiform bAVMs and underwent detailed pretreatment diagnostic cerebral angiography at our medical center from 1996 to 2006. All patients had superselective microcatheter angiography, and films were reviewed for the purpose of this project. Patient demographics, clinical presentation, and angioarchitectural characteristics were analyzed. A univariate analysis was performed, and angioarchitectural features with potential physiological significance that showed at least a trend toward significance were added to a multivariate logistic regression model. RESULTS: One hundred twenty-two bAVMs met criteria for study entry. bAVMs with single venous drainage anatomy were more likely to present with hemorrhage. In addition, patients with multiple draining veins and a venous stenosis reverted to a risk similar to those with 1 draining vein, whereas those with multiple draining veins and without stenosis had diminished association with hemorrhage presentation. Those bAVMs with associated aneurysms were more likely to present with hemorrhage. These findings were robust in both univariate and multivariate models. CONCLUSIONS: The results of this article lead to the first physiological, internally consistent model of individual bAVM hemorrhage risk, where 1 draining vein, venous stenosis, and associated aneurysms increase risk.
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Hemorragia Cerebral/etiología , Aneurisma Intracraneal/complicaciones , Malformaciones Arteriovenosas Intracraneales/complicaciones , Modelos Biológicos , Adulto , Factores de Edad , Angiografía Cerebral , Constricción Patológica/complicaciones , Constricción Patológica/diagnóstico por imagen , Femenino , Humanos , Aneurisma Intracraneal/diagnóstico por imagen , Malformaciones Arteriovenosas Intracraneales/clasificación , Malformaciones Arteriovenosas Intracraneales/diagnóstico por imagen , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Venas/patologíaRESUMEN
OBJECTIVES: To assess whether (1)H-MRS may be useful to reinforce the radiological suspicion of PCNSL. METHODS: In this retrospective study, we included 546 patients with untreated brain tumours in which single-voxel spectroscopy at TE 30 ms and 136 ms had been performed. The patients were split into two subgroups: "training set" and "test set." Differences between PCNSL and five other types of intracranial tumours were assessed in the test set of patients using the Mann-Whitney U nonparametric test and cut-off values for pair-wise comparisons defined by constructing receiver operating characteristic curves. These thresholds were used to construct classifiers for binary comparison between PCNSL and non-PCNSL. The performance of the obtained classifiers was assessed in the independent test set of patients. RESULTS: Significant differences were found between PCNSL and the other groups evaluated. All bilateral comparisons performed in the test set obtained accuracy values above 70 % (71-89 %). Lipids were found to be useful to discriminate between PCNSL and glioblastoma/metastasis at short TE. Myo-inositol resonance was found to be very consistent for discriminating between PCNSL and astrocytomas at short TE. CONCLUSIONS: (1)H-MRS is useful to reinforce diagnostic suspicion of PCNSL on MRI. KEY POINTS: ⢠(1) H-MRS can be used to reinforce the diagnostic suspicion of PCNSL. ⢠Lipids can be used to discriminate between PCNSL and GB/MET. ⢠Myo-inositol resonance can be used to discriminate between PCNSL and astrocytomas.
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Neoplasias del Sistema Nervioso Central/diagnóstico , Linfoma/diagnóstico , Espectroscopía de Resonancia Magnética/métodos , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Neoplasias del Sistema Nervioso Central/cirugía , Diagnóstico Diferencial , Femenino , Estudios de Seguimiento , Humanos , Linfoma/cirugía , Imagen por Resonancia Magnética/métodos , Masculino , Persona de Mediana Edad , Periodo Preoperatorio , Curva ROC , Reproducibilidad de los Resultados , Estudios Retrospectivos , Adulto JovenRESUMEN
The skull vault, formed by the flat bones of the skull, has a limited spectrum of disease that lies between the fields of neuro- and musculoskeletal radiology. Its unique abnormalities, as well as other ubiquitous ones, present particular features in this location. Moreover, some benign entities in this region may mimic malignancy if analyzed using classical bone-tumor criteria, and proper patient management requires being familiar with these presentations. This article is structured as a practical review offering a systematic diagnostic approach to focal calvarial lesions, broadly organized into four categories: (1) pseudolesions: arachnoid granulations, meningo-/encephaloceles, vascular canals, frontal hyperostosis, parietal thinning, parietal foramina, and sinus pericrani; (2) lytic: fibrous dysplasia, epidermal inclusion and dermoid cysts, eosinophilic granuloma, hemangioma, aneurysmal bone cyst, giant cell tumor, metastasis, and myeloma; (3) sclerotic: osteomas, osteosarcoma, and metastasis; (4) transdiploic: meningioma, hemangiopericytoma, lymphoma, and metastasis, along with other less common entities. Tips on the potential usefulness of functional imaging techniques such as MR dynamic susceptibility (T2*) perfusion, MR spectroscopy, diffusion-weighted imaging, and PET imaging are provided.
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The sex of sea turtles is determined by temperature during egg incubation. Thus, climate change affects the sex ratio, exacerbating their vulnerability to extinction. Understanding spatiotemporal effects of temperature on sex determination at the gonadal level may facilitate the design of strategies to mitigate the effects of global warming. Here, we used qRT-PCR and immunofluorescence to analyze the spatiotemporal expression of Dmrt1 and Foxl2 in developing gonads of Lepidochelys olivacea incubated at male-producing temperature (MPT, 26°C) or female-producing temperature (FPT, 33°C). Although both transcription factors are expressed in bipotential gonads up to stage 25, the timing of their sexually dimorphic regulation differs. Whereas the dimorphic expression of Dmrt1 protein initiates at stage 24, Foxl2 protein was expressed specifically in females at stage 25. Interestingly, whereas Dmrt1 colocalizes with Sox9 in cell nuclei of primary medullary cords to form the testis cords, Foxl2 protein is first detected in Sox9-negative cells of primary medullary cords, prior to its substantial expression in the ovarian cortex. Thus, results suggest that the temperature-dependent regulation of sexual pathways is stochastic among the cells of primary medullary cords in undifferentiated bipotential gonads of the olive ridley.
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BACKGROUND AND PURPOSE: Recent reports have indicated that mechanical thrombectomy may have potential to treat acute ischemic stroke. However, few comparative studies of neurothrombectomy devices are reported. This study aims to compare the safety and effectiveness of two retrievable stent systems in acute ischemic stroke patients. METHODS: A prospective study comparing the clinical, radiological, and functional outcome of 33 patients with an angiographically verified occlusion of the anterior cerebral circulation. Patients were treated either with Trevo Retriever(TM) or Solitaire Stent(TM) according to the neurointerventionalist preference. Successful recanalization was defined as TICI grade 2a to 3. Good outcome was defined as a modified Rankin Scale score ≤ 2 at 3 months. RESULTS: Revascularization was achieved in 10 patients (77%) in the Trevo group and in 12 (60%) of the Solitaire group (P = .456). Rate of symptomatic ICH was 0% for Trevo versus 15% for Solitaire (P = .261). Four patients (30%) died during the 3-month follow-up period in the Trevo versus 5 patients (25%) in the solitaire group (P = 1.000). Rate of good outcome was 38% and 40% for Trevo and Solitaire respectively (P = .435). CONCLUSIONS: Our study showed no significant differences between both stentrievers. Moderately high recanalization rates are possible with both, however larger series may depict safety-related variations.
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Prótesis Vascular , Infarto de la Arteria Cerebral Anterior/terapia , Infarto de la Arteria Cerebral Media/terapia , Stents , Trombectomía/instrumentación , Anciano , Remoción de Dispositivos/instrumentación , Remoción de Dispositivos/métodos , Análisis de Falla de Equipo , Femenino , Humanos , Infarto de la Arteria Cerebral Anterior/diagnóstico por imagen , Infarto de la Arteria Cerebral Media/diagnóstico por imagen , Masculino , Diseño de Prótesis , Radiografía , Trombectomía/métodos , Resultado del TratamientoRESUMEN
BACKGROUND AND PURPOSE: Recent reports have indicated that mechanical thrombectomy may have the potential to treat acute ischemic stroke. This study aims to describe the safety and effectiveness of Trevo Retriever, using Stentriever technology, in revascularization of patients with acute ischemic stroke. METHODS: Prospective study evaluating the clinical, radiological, and functional outcome of 13 patients with an angiographically verified occlusion of the anterior cerebral circulation. All patients underwent thrombectomy with TR as monotherapy or in combination with intra-arterial thrombolysis, within the first 8 hours from the onset of symptoms. Successful revascularization was defined as thrombolysis in cerebral ischemia grade 2a to 3. Good outcome was defined as modified Rankin Scale score ≤ 2. RESULTS: Median baseline National Institutes of Health Stroke Scale score was 19(16-22). The occlusion site was middle cerebral artery in 8 patients and internal carotid artery in 5 patients. Revascularization was achieved in 10 of 13 patients (77%). The mean time from groin puncture to recanalization was 95 ± 31 minutes. No significant intra-procedural complications occurred. Four patients (30%) died during the 90-day follow-up period and 4 patients (30%) achieved functional independence. CONCLUSION: Early clinical experience suggests that the TR can allow safe and effective revascularization in certain subjects with acute ischemic stroke.
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Isquemia Encefálica/diagnóstico por imagen , Isquemia Encefálica/cirugía , Angiografía Cerebral/métodos , Trombolisis Mecánica/instrumentación , Radiografía Intervencional/métodos , Accidente Cerebrovascular/diagnóstico por imagen , Accidente Cerebrovascular/cirugía , Anciano , Anciano de 80 o más Años , Isquemia Encefálica/complicaciones , Diseño de Equipo , Análisis de Falla de Equipo , Femenino , Humanos , Masculino , Trombolisis Mecánica/métodos , Persona de Mediana Edad , Accidente Cerebrovascular/etiología , Resultado del TratamientoRESUMEN
OBJECT: Nidal embolization of brain arteriovenous malformations (bAVMs) has become an increasingly important component of bAVM treatment. However, controversy exists as to the relative efficacy and safety of single-stage versus multistage approaches to bAVM embolization, with recent literature favoring multistage strategies. The authors present a series of consecutive bAVMs embolized at their institution, demonstrating the safety and efficacy of a predominantly single-stage embolization strategy. The safety and efficacy of embolization are reported in the context of predetermined treatment strategies to provide more generalizable insight into treatment outcome. METHODS: One hundred thirty consecutive patients with 131 bAVMs underwent endovascular embolization at a single center. Diagnostic angiography with superselective microcatheterizations was performed in all patients. Postembolization angiograms were reviewed by 3 neuroradiologists for degree of occlusion and angiographic evidence of procedural complications. Patients were divided into cohorts based on the prospectively determined treatment strategy, which included the following: global devascularization of the bAVM (Devasc); targeting of a focal angioarchitectural weakness (Target), typically as an adjunct to surgery or Gamma Knife treatment; and primary occlusion of the bAVM by embolization alone (Occlude). Safety and efficacy were evaluated in the context of these treatment groups. RESULTS: The 131 bAVMs were treated over an average of 1.28 embolization sessions per bAVM; 105 bAVMs (80%) were treated in a single stage. The average percentage devascularization in the Devasc arm was 85.3%, which was statistically significantly greater than the 72% aggregate devascularization reported in 8 modern N-butyl cyanoacrylate and Onyx papers based on 1-sample Wilcoxon rank-sum testing (p<0.001). Focal angioarchitectural weaknesses were successfully embolized for all 24 bAVMs in the Target group, directly with the embolic agent in 23 bAVMs and indirectly in 1 bAVM with a venous aneurysm/pseudoaneurysm by reducing arterial inflow and inducing venous thrombosis. Lesions in all patients in the Occlude arm were 100% occluded with embolization alone. Overall, the bAVMs in the Occlude arm were significantly smaller and required embolization of fewer pedicles than those in the Devasc group. One patient (0.8%) experienced significant morbidity following embolization, and 1 patient in the cohort died (0.8%). CONCLUSIONS: This research communicates the authors' experience in developing a largely single-stage strategy for embolization of bAVMs. The results suggest that an aggressive, single-stage embolization may be implemented with a margin of safety and effectiveness similar to the multistage approaches more commonly reported in the literature. This work additionally introduces the importance of prospective assignment to a treatment strategy in assessing procedural outcome in bAVM embolization, thereby improving generalizability of the results and allowing for more rigorous interpretation of efficacy and safety.